Block processing of input data in graphical programming environments

ABSTRACT

In one embodiment, a processing block of a block diagram receives input data including a plurality of data elements organized as a matrix of a first size. At least a portion of the input data is partitioned into a plurality of data blocks in response to user-selected parameters. A data block includes selected ones of the plurality of data elements organized as a matrix of a second size. The data processing block performs a data processing function on the plurality of data blocks in a user-specified order to yield processed data corresponding to each data block. The processed data corresponding to each data block is then reassembled to form output data corresponding to the input data and the output data is output from the processing block to another block of the block diagram.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of copending U.S. patent application Ser. No. 10/744,654, which was filed on Dec. 22, 2003, by Houman Zarrinkoub et al., for BLOCK PROCESSING OF INPUT DATA IN GRAPHICAL PROGRAMMING ENVIRONMENTS.

FIELD OF THE INVENTION

The present invention relates generally to graphical programming environments and more particularly to methods and systems for performing block processing of input data in the graphical programming environments. In the block processing of input data, the input data are partitioned into a plurality of data blocks, which are smaller sections of the input data, and each of the data block is processed.

BACKGROUND OF THE INVENTION

Various classes of block diagrams describe computations that can be performed on application specific computational hardware, such as a computer, microcontroller, FPGA, and custom hardware. Classes of such block diagrams include time-based block diagrams, such as those found within Simulink®, from The MathWorks, Inc. of Natick, Mass., state-based and flow diagrams, such as those found within Stateflow®, from The MathWorks, Inc. of Natick, Mass., and data-flow diagrams. A common characteristic among these various forms of block diagrams is that they define semantics on how to execute the diagram.

Historically, engineers and scientists have utilized time-based block diagram models in numerous scientific areas such as Feedback Control Theory and Signal Processing to study, design, debug, and refine dynamic systems. Dynamic systems, which are characterized by the fact that their behaviors change over time, are representative of many real-world systems. Time-based block diagram modeling has become particularly attractive over the last few years with the advent of software packages, such as Simulink®. Such packages provide sophisticated software platforms with a rich suite of support tools that makes the analysis and design of dynamic systems efficient, methodical, and cost-effective.

A dynamic system (either natural or man-made) is a system whose response at any given time is a function of its input stimuli, its current state, and the current time. Such systems range from simple to highly complex systems. Physical dynamic systems include a falling body, the rotation of the earth, bio-mechanical systems (muscles, joints, etc.), bio-chemical systems (gene expression, protein pathways), weather and climate pattern systems, etc. Examples of man-made or engineered dynamic systems include: a bouncing ball, a spring with a mass tied on an end, automobiles, airplanes, control systems in major appliances, communication networks, audio signal processing, nuclear reactors, a stock market, etc. Professionals from diverse areas such as engineering, science, education, and economics build mathematical models of dynamic systems in order to better understand system behavior as it changes with the progression of time. The mathematical models aid in building “better” systems, where “better” may be defined in terms of a variety of performance measures such as quality, time-to-market, cost, speed, size, power consumption, robustness, etc. The mathematical models also aid in analyzing, debugging and repairing existing systems (be it the human body or the anti-lock braking system in a car). The models may also serve an educational purpose of educating others on the basic principles governing physical systems. The models and results are often used as a scientific communication medium between humans. The term “model-based design” is used to refer to the use of block diagram models in the development, analysis, and validation of dynamic systems.

The graphical programming environments may provide tools for implementing data processing systems that generally consist of a cascade of components performing a series of data operations to input data in order to obtain a set of desired output data. In most applications, such data processing systems are required to carry out the processing of the input data in real time to produce the output data.

In many applications including image or video processing systems, the input data have the dimensions of a matrix and includes a large amount of data to be processed. Temporary storage of the processed copies of such large signals imposes a heavy burden in terms of memory use. Alternatively, we can perform the operation by breaking down the input signal into smaller segments called data blocks, applying the same processing on each data block and reconstruct the processed signal. This kind of operation is known as block processing. Since the size of the data block is much smaller than the input signal, in block processing the requirements in terms of temporary memory use are greatly reduced.

SUMMARY OF THE INVENTION

The present invention provides methods and systems for performing block processing of input data in graphical programming environments. In the block processing of the present invention, the input data may have any dimensionality. The input signal that is to be processed is partitioned into a plurality of data blocks. Users may specify how to divide the input data into data blocks, for example, by designating the size of the input data to be processed and the size of the data blocks the input signal is partitioned into a total number of data blocks to be processed. Users may also designate a data processing function for processing each block of the input data. The blocks of the processed data are reassembled to generate output data. If the size of the output data is smaller than or equals to the size of the input data, the present invention is able to perform in-place block processing of the input data in which the blocks of the processed data are overwritten on the blocks of the input data. The output data may share memory space with the input data so that the block processing of the present invention saves memory space in processing the input data.

In accordance with one aspect of the present invention, a method is provided for performing block processing of input data in an electronic device that provides graphical programming environments. A graphical element is displayed on the display of the electronic device so that the graphical element receives the input data. The graphical element represents a block processing model that performs block processing of the input data. In response to an action taken by users in connection with the graphical element, a user interface is provided for entering control data of the block processing model. The control data set up an operation mode of the block processing model. The block processing model performs block processing of the input data based on the control data of the block processing model.

In another aspect of the present invention, a method is provided for performing block processing of input data in an electronic device that provides graphical programming environments. The input data is partitioned into blocks based on control data entered by users. An index is generated for a block of the input data to specify the block in the input signal. The data block is selected based on the index of the block and processed. The processed data is assigned to a location in the output data, in which the location of the processed data in the output data is determined by the index of the block.

In still another aspect of the present invention, a system is provided for performing block processing of input data. The system is implemented in an electronic device that provides graphical programming environments. The system includes an iterator for receiving the input data and dividing the input data into a plurality of data blocks. The system also includes a data processing unit for processing a block of the input data. The iterator enables the data processing unit to repeat the data processing of the input data on each of the blocks.

In yet still another aspect of the present invention, a system is provided for performing block processing of input data in an electronic device that provides graphical programming environments. The system includes a pointer generator for iteratively generating a pointer of each block of the input data. The system also includes a data processing unit for processing each block of the input data designated by the pointer. The pointer represents a location of each data block in memory space.

By providing block processing of input data, the present invention enables the processing of a large amount of data in real time. In addition, the present invention enables in-place processing of the input data when the size of the input data is larger than or equals to the size of the output data. As a result, the present invention saves memory space in processing the input data.

BRIEF DESCRIPTION OF THE DRAWINGS

The aforementioned features and advantages, and other features and aspects of the present invention, will become better understood with regard to the following description and accompanying drawings, wherein:

FIG. 1 is an exemplary graphical programming environment that utilizes blocks to represent models in the illustrative embodiment of the present system;

FIG. 2 is an electronic device suitable for practicing the illustrative embodiment of the present invention;

FIG. 3 is an exemplary block for use in a block processing model provided in the graphical programming environment of the illustrative embodiment of the present invention depicted in FIG. 1;

FIG. 4 is an exemplary graphical user interface (GUI) for entering the parameters of a block processing block to set up the operation mode of the block processing block in the illustrative embodiment of the present invention depicted in FIG. 3;

FIG. 5A is an example of input data illustrating the overlapped rows and columns of each block entered through the GUI depicted in FIG. 4 in the illustrative embodiment of the present invention;

FIG. 5B is an example of input data illustrating the padding process of input data in the illustrative embodiment of the present invention;

FIG. 5C is an example of input data illustrating the horizontal (row-wise) order of blocks traversing input data in the illustrative embodiment of the present invention;

FIG. 5D is an example of input data illustrating the vertical (column-wise) order of blocks traversing input data in the illustrative embodiment of the present invention;

FIG. 5E is an example of input data illustrating the zigzag order of blocks traversing input data in the illustrative embodiment of the present invention;

FIG. 6 is an exemplary block processing block in the illustrative embodiment of the present invention;

FIG. 7 is another exemplary block processing block in the illustrative embodiment of the present invention; and

FIG. 8 is still another exemplary block processing block in the illustrative embodiment of the present invention.

DETAILED DESCRIPTION

The illustrative embodiment of the present invention concerns graphical programming environments, such as block diagram programming environments, provided on an electronic device. Block diagrams are the representations of real-world systems through graph containing nodes (called blocks) interconnected by arcs (called lines). Blocks are functional entities that perform operations on the data being processed by the systems. The lines represent data (called signals) being communicated between the various blocks. One of skill in the art will appreciate that the block diagrams are an illustrative graphical programming environment and the present invention may apply to other types of graphical programming environments, such as state flowchart programming environments.

The graphical programming environments of the illustrative embodiment of the present invention provide a block processing block that performs the block processing of input data. The block processing block is a functional node in the block diagram environment, which processes input data in sections called data blocks (smaller sections of the input signals), rather than the entire input data at once. The block processing block receives the input data and divides into blocks the input data that is to be processed by the block processing block. The block processing block iteratively processes each block of the input data and combines the resulting blocks of the processed data to generate output data. One of skill in the art will appreciate that although the block processing block is provided in a single block in the illustrative embodiment of the present invention, the block processing may be implemented in multiple blocks that may include the components of the block processing block.

The block processing block performs the data processing of input data in blocks depending on the users' selection of the operation mode of the block processing block. The operation mode of the block processing block is determined by users entering the parameters of the block processing block, such as the size of data blocks, the size of input data to be processed, etc. The block processing block may perform in-place processing of the input data if the size of the output data is smaller than or equals to the size of the input data. In the in-place block processing of the input data, the blocks of the processed data are overwritten on the blocks of the input data. As a result, the output data shares memory space with the input data to save the memory space for the output data.

FIG. 1 is an exemplary graphical programming environment in which blocks are utilized to represent models in the illustrative embodiment of the present invention. The environment 100 includes a block library block 110, an editor 120, a simulator 130 and a code generator 140. The code generator 140 may generate source code for the models in the illustrative embodiment of the present invention.

The block library 110 contains blocks of application specific models that support the modeling and simulation of systems. The blocks in the block library 110 are incorporated into the models of the systems designed using the modeling and simulation tool 130. The blocks provided from the block library 100 are represented in rectangular blocks in the illustrative embodiment of the present invention. One of skill in the art will appreciate that the models can be represented in other graphical symbols or textual symbols. The model blocks provided by the block library 110 include a block processing block 300 (see FIG. 3) for processing input data in blocks. The block library 110 may also include the component blocks of the block processing block that may be combined to implement a block processing function. One of skill in the art will appreciate that the block processing in the illustrative embodiment of the present invention may implemented in multiple blocks that may include the components of the block processing block. An illustrative embodiment of the block library 110 may be found in Simulink® Blocksets, such as DSP Blockset, Fixed-point Blockset and Communications Blockset, from The MathWorks, Inc. of Natick, Mass. The Blocksets provide models and utilities for the development and integration of models for target systems and sub-systems of the target systems.

The editor 120 and simulator 130 provide graphical simulation and prototyping environment for modeling, simulating, and analyzing target systems. The editor 120 incorporates the blocks provided from the block library 110 into the target systems. The target systems designed in the editor 120 are simulated by the simulator 130 to analyze the behavior of the designed target systems. Exemplary editor 120 and simulator 130 may be found in Simulink®, from The MathWorks, Inc. of Natick, Mass. The Blockset operates in Simulink®.

Simulink® enables users to design a block diagram for a target system, simulate the system's behavior, analyze the performance of the system, and refine the design of the system. Simulink® allows users to design target systems through a user-interface that allows drafting of block diagram models of the target systems. All of the blocks in the block library 110 are available to users when the users are building the block diagram of the target systems. Individual users may be able to customize this model block to: (a) reorganize blocks in some custom format, (b) delete blocks they do not use, and (c) add custom blocks they have designed. The blocks may be dragged through some human-machine interface (such as a mouse or keyboard) from the block library 110 on to the window (i.e., model canvas). Simulink® includes a block diagram editor that allows users to perform such actions as draw, edit, annotate, save, and print out block diagram representations of target systems. The block diagram editor is a graphical user interface (GUI) component that allows drafting of block diagram models by users. In Simulink®, there is also a textual interface with a set of commands that allow interaction with the graphical editor. Using this textual interface, users may write special scripts that perform automatic editing operations on the block diagram. Simulink® also allows users to simulate the designed target systems to determine the behavior of the systems. Simulink® includes a block diagram execution engine that carries out the task of compiling and linking the block diagram to produce an “in-memory executable” version of the model that is used for generating code and/or simulating a block diagram model.

The code generator 140 generates customizable C-code directly from the block diagrams of the models designed using the editor 120. By automatically generating source code, the code generator 140 enables rapid prototyping, hardware-in-the-loop simulations, and desktop rapid simulation of the models designed in the editor 120. The code generation tool 140 may generate efficient source code for embedded systems applications. One of skill in the art will appreciate that source code is an illustrative code that is generated in the code generator 140 and the code generator 140 may generate different code for the models, such as Ada. Real-Time Workshop from The MathWorks, Inc. of Natick, Mass., is an exemplary code generation tool 140.

One of skill in the art will appreciate that the graphical programming environment 100 is not limited to block diagram programming environments, but rather includes any other graphical programming environments, such as state flowchart graphical programming environments. Stateflow® from The MathWorks, Inc. of Natick, Mass., provides an exemplary state flowchart modeling environment. Stateflow® provides a graphical environment for modeling and designing event-driven models. Stateflow® enables users to generate state flowcharts that graphically represent hierarchical and parallel states and the event-driven transitions between the states of the models. Simulink® that is seamlessly interfaced with Stateflow® may execute the models and analyze the behavior of the models based on the state flowcharts created in Stateflow®.

FIG. 2 is an exemplary electronic device 200 suitable for practicing the illustrative embodiment of the present invention. The electronic device 200 includes a network interface 230, a MODEM 240, a secondary memory 250, a primary memory 260, a microprocessor 270, a monitor 280 and a keyboard/mouse 290. The microprocessor 270 controls each component of the electronic device 200 to run the software tools in the graphical programming environment 100 properly. The electronic device 200 receives the data necessary for controlling the design and simulation of a target system through the keyboard/mouse 290, such as the control data to set up the operation modes of the block processing block 300 (see FIG. 3). The electronic device 200 displays in the monitor 280 the result generated in the graphical programming environment 100. The primary memory 260 fetches from the secondary memory 250 and provides to the microprocessor 270 the codes that need to be accessed quickly by the microprocessor 270 to operate the electronic device 200 and to run the graphical programming environment 100. The secondary memory 250 usually contains software tools for applications. The secondary memory 250 includes, in particular, code 251 for the block library 110, code 252 for the editor 120, and code 253 for the simulator 130. The network interface 230 and the MODEM 240 enable the electronic device 200 to communicate with other electronic devices through communication networks, such as Internet, intranet, LAN (Local Area Network), WAN (Wide Area Network) and MAN (Metropolitan Area Network). The communication facilities may support for the distributed implementations of the present invention.

FIG. 3 is an exemplary block processing block 300 provided by the block library 110 in the graphical programming environment 100 of the illustrative embodiment of the present invention depicted in FIG. 1. The block processing block 300 implements an iterative system within a graphical programming environment that is capable of performing the block processing operation. The block processing block 300 receives input data and generates output data. The input data may have any dimensionality. In image or video data processing systems, for example, the input data has the dimension of a matrix and includes a large amount of data to be processed. The block processing block 300 includes a sub-block that represents a data processing unit 310 performing a data processing function on the input data. The data processing function of the data processing unit 310 maybe specified by users. For example, the block processing block 300 processes each 8×8 block of the 512×512 input data with a single DCT (Discrete Cosine Transform) data processing unit 310.

The block processing block 300 partitions the input data into blocks, sends each block of the input data to the data processing unit 310, and forms the output data by placing each block of the processed data at an appropriate location in the output data. The operation mode of the block processing block 300 is determined by users specifying the parameters of the block processing block 300, such as the size of the blocks and the range of input data over which block processing is performed. The parameters of the block processing block 300 are described in more detail with reference to FIG. 4. Based on the pre-determined operation mode of the block processing block 300, the entire input data or a portion of the input data is partitioned into blocks. A data processing function is operated on each block of the input data by the data processing unit 310. The output data is reconstituted by reassembling the blocks of the processed data in the same order as the blocks of the input data are processed.

The block processing block 300 may be utilized in many applications including image compression and speech coding. In JPEG (Joint Photographic Expert Group) image compression, the data processing unit 310 may be selected to perform JPEG image compression algorithm so that a large amount of input image data may be compressed utilizing the block processing. In compression phases, the input image is partitioned into blocks and each block is processed by the data processing unit 310 that performs a DCT (Discrete Cosine Transform) transform. In decompression phases, the inverse DCT is applied on each block and finally the output data is reconstructed. One of skill in the art will appreciate that the block processing block 300 may be used in MPEG (Moving Picture Experts Group) video compression. In speech coding applications, the speech signal is processed within a frame of 10-30 ms. Usually the input frame is sub-divided into 2 to 4 sub-frames where the data processing unit 310 may perform same sets of operations on the samples of the sub-frames. The speech coding sub-frames may have overlapping samples across the sub-frame boundaries. The overlap is described below in more detail with reference to FIG. 5A.

FIG. 4 is an exemplary graphical user interface (GUI) 400 for entering the parameters of the block processing block 300 to set up the operation mode of the block processing block 300 in the illustrative embodiment of the present invention depicted in FIG. 3. One of skill in the art will appreciate that the GUI 400 is illustrative and the parameters of the block processing block 300 may be input through a textual user interface, such as a command line interface. The GUI 400 provides some blanks for users to input the parameters of the block processing block 300. The parameters may include the number of rows per block 410, the number of columns per block 420, overlapped rows 430, overlapped columns 440, the size of input data 450, and boundary values 460. One of skill in the art will appreciate that the parameters provided in the GUI 400 are illustrative and the GUI 400 may provide blanks to input additional parameters, such as the data processing function of the data processing unit 310 and the order of blocks traversing the input data. The order of blocks traversing the input data will be described below in more detail with reference to FIGS. 5C-5E.

The number of rows per block 410 and the number of columns per block 420 determine the size of blocks in the input data. One of skill in the art will appreciate that the GUI 400 may include a different set of parameters to determine the size of blocks, such as the number of blocks along the rows of the input data to be processed and the number of blocks along the columns of the input data to be processed.

The overlapped rows 430 and overlapped columns 440 determine the overlaps of each block with adjacent blocks. The overlaps are extra rows and columns of outside a data block whose values are taken into account when processing the block. FIGS. 5A is an exemplary input data illustrating the overlapped rows and columns of each block in the input data. In FIG. 5A, the input data is partitioned into data blocks, where these data blocks have a size of an 8 by 8 matrix in the illustrative embodiment of the present invention. Each block of the input data has overlapped with adjacent blocks by 2 columns and a row. Each 8 by 8 block has a one-row overlap above and below, and a two-column overlaps on each side. The shaded portion 520 indicates the overlap. The GUI 400 may include a blank to input boundary values 460 for padding. FIG. 5B is an exemplary input data illustrating the padding process of the input data in the illustrative embodiment of the present invention. The input data is partitioned into blocks and each of blocks has an 8 by 8 matrix. If the blocks don't fit exactly over the input data, padding values are added to the shaded area 530, the bottom and right of the input data, so that the blocks match with the input data to be processed. In addition, the overlaps shown in FIG. 5A are extended beyond the boundary 510 of the input data. The padding process also adds the padding values to the overlap 520 outside the boundary 510 of the input data.

Users may select the order of the blocks traversing the input data to be processed by selecting an index generator, which is a codeword generating function. The data blocks may be traversed with any arbitrary ordering specified by the user. For example, the blocks may be processed in a horizontal (row-wise), vertical (column-wise) or zigzag direction, as depicted in FIGS. 5C-5E, respectively. One of skill in the art will appreciate that the orders shown in FIGS. 5C-5E are illustrative and the blocks may be traversed in other orders, such as diagonal and anti-diagonal directions. The blocks may also be processed in a user-defined order. For example, if users input a specific order for processing the blocks, for example [1, 3, 5, 7, 9, . . . ], the blocks of the input data are processed in the order of Block 1, Block 3, Block 5, Block 7, Block 9, . . . .

FIG. 6 is an exemplary block processing block 600 that performs block processing of input data in the illustrative embodiment of the present invention. The block processing block 600 includes an iterator 610 and a data processing unit 620. The iterator 610 receives the input data, and generates output data. Based on the operation mode of the block processing block 600 selected by users, the iterator 610 selects a block of the input data to be processed and transfers the selected block of the input data to the data processing unit 620. The data processing unit 620 processes the selected block of the input data and returns a block of processed data to the iterator 610 that in turn places the block of the processed data in the output data. The current block under processing may be visually depicted within the environment 100. This depiction may be useful in debugging operation. One of skill in the art will appreciate that the block of the processed data may have a different size than the block of input data depending on the data processing function of the data processing unit 620 defined by users. The location of the block of the processed data in the output data is determined based on the location of the selected block in the input data. The block processing block 600 iterates these steps with all of the blocks of the input data to be processed.

FIG. 7 is another exemplary block processing block 700 that performs block processing of input data in the illustrative embodiment of the present invention. The block processing block 700 includes an index generator 710, a selector 720, a data processing unit 730 and an assignment unit 740. The selector 720 and the assignment unit 740 receive the input data and the assignment unit 740 produces output data. The index generator 710 generates code-words or indices for the blocks of the input data that generally contain one or more integers. Based on the operation mode of the block processing block, the index generator 710 generates iteratively a series of code-words or indices that specify exactly what elements of the input data are selected to form a block in the iteration of the bock processing. The indices of the blocks are determined to specify both of the blocks of the input data to be processed and the locations of the blocks of the processed data in the output data. The indices of the blocks generated by the index generator may be a scalar or a vector. The block index uniquely identifies all samples contained in the block. The scalar or vector index is necessarily of reduced dimensionality with respect to the dimension of the data block. The index generator is capable of a generalized addressing scheme to uniquely identify the sub-units of the input signal. In this generalized addressing scheme, the samples composing the sub-units of the input signal may not necessarily be adjacent elements in memory. Let i=1, 2, 3, . . . , n be the index of the iteration, the address of the sub-unit elements can be any function f(i) applied to the iteration index. For example, the block index codeword may be defined as a simple linear function of i, f(i)=a+bi, where a is a starting index and b is an index increment. Another exemplary index of a block may include [starting row, ending row] and [starting column, ending column] of the block. One of skill in the art will appreciate that the index may be in different forms, for example, using the offsets of the ending row/column from the starting row/column of each block. The selector 720 and assignment unit 740 receives the indices of the blocks of the input data. The selector 720 selects a block based on the index of the block and transfers the selected block to the data processing unit 730. The data processing unit 730 processes the transferred block of the input data and outputs a block of processed data. The assignment unit 740 receives the block of the processed data and assigns the block of the processed data in the output data based on the index of the block of the input data. One of skill in the art will appreciate that different index generators may be used for the selector 720 and the assignment unit 740. The block processing block 700 iterates these steps with all of the blocks of the input data to be processed. The block processing block 700 may perform in-place processing of the input data, which requires the output data to share memory space with the input data. In the in-place processing, output data is overwritten on the input data. The in-place block processing is described below in more detail with reference to FIG. 8.

FIG. 8 is still another exemplary block processing block 800 that may perform in-place block processing of input data in the illustrative embodiment of the present invention. The block processing block 800 includes a pointer generator 810 and a data processing unit 820. The pointer generator 810 and the data processing unit 820 receive the input data. Based on the operation mode of the block processing block 800 selected by users, the pointer generator 810 generates a pointer to each block of the input data. The pointer to a block of the input data represents the location of the block in memory space. The pointer of the block may include a pointer to the first element of the block. One of skill in the art will appreciate that the pointer to the block may include a pointer to other elements of the block that can specify the block in the memory space, such as a pointer to the last element of the block. The pointer to the block of the input data is passed to the data processing unit 820. The data processing unit 820 processes the block of the input data specified by the pointer. On the completion of processing the block of the input data, the data processing unit 820 overwrites the block of the processed data on the location in memory space specified by the pointer to the block received from the pointer generator 810. The bock processing block 800 iterates these steps with all of the blocks of the input data to be processed. Hence at the end of the iterative process, output data is completely formed. One of skill in the art will appreciate that in the in-place processing of the input data, the size of the input data is generally larger than or equals to the size of the output data.

In summary, the illustrative embodiment of the present invention provides block processing of input data in graphical programming environments. The illustrative embodiment of the present invention provides a block processing block that performs the block processing of the input data. One of skill in the art will appreciate that the block processing of the input data may be implemented in multiple blocks that are the components of the block processing block. The portion to be processed in the input data is partitioned into blocks and the blocks of the input data are processed in an order designated by users. The blocks of the processed data are combined in a same order as the blocks of the input data are processed. The illustrative embodiment of the present invention also provides in-place block processing of the input data, in which the blocks of the processed data are overwritten on the memory space corresponding to the blocks of the input data. The in-place processing of the input data enables the output data to share memory space with the input data and save memory space for the output data.

It will thus be seen that the invention attains the objectives stated in the previous description. Since certain changes may be made without departing from the scope of the present invention, it is intended that all matter contained in the above description or shown in the accompanying drawings be interpreted as illustrative and not in a literal sense. For example, the illustrative embodiment of the present invention may be practiced in any graphical programming environment that provides data processing of input data. Practitioners of the art will realize that the sequence of steps and architectures depicted in the figures may be altered without departing from the scope of the present invention and that the illustrations contained herein are singular examples of a multitude of possible depictions of the present invention. 

1. A method for executing a block diagram of a graphical programming environment, comprising: receiving input data at a processing block of the block diagram, the input data including a plurality of data elements organized as a matrix of a first size, the first size defining at least two rows and at least two columns of the data elements; partitioning at least a portion of the input data into a plurality of data blocks in response to user-selected parameters, a data block including selected ones of the plurality of data elements and organized as matrix of a second size; performing a data processing function on the plurality of data blocks in an order specified by a user to yield processed data corresponding to each data block of the plurality, the order being one of a plurality orders that may be specified; reassembling the processed data corresponding to each data block to form output data corresponding to the input data; and outputting the output data from the processing block to another block of the block diagram.
 2. The method of claim 1 further comprising: generating a unique codeword for a particular data block; and using the unique codeword for the particular data block to generate an address a data element included in the particular data block.
 3. The method of claim 2 wherein the unique codeword is a linear function that may be represented in the form f(i)=a+bi, where f(i) is the address of a data element, a is a starting index, b is an index increment, and i is an index of iteration.
 4. The method of claim 1 wherein the selected parameters comprise at least one of a user-selected number of rows or a user-selected number of columns, that defines the second size.
 5. The method of claim 1 wherein the selected parameters comprise a user-selected range that specifies the portion of the input data partitioned into the plurality of data blocks.
 6. The method of claim 1 wherein the step of partitioning further comprises: overlapping at least one row of data elements or at least one column of data elements of a data block with data elements of another data block, such that some data elements are included in multiple data blocks
 7. The method of claim 1 further comprising: adding at least one row or at least one column of padding data elements to the input data, before the step of partitioning.
 8. The method of claim 1 wherein the step of reassembling further comprises: overwriting at least a portion of the input data with the processed data corresponding to a data block to perform in-place data processing.
 9. The method of claim 1 wherein the input data describes an input image and a data block corresponds to a portion of the input image, and the step of performing applies a compression algorithm the portions of the input image.
 10. A computer-readable storage media comprising code for executing a block diagram of a graphical programming environment, the code executable by a computer to: receive input data at a processing block of the block diagram, the input data including a plurality of data elements; partition at least a portion of the input data into a plurality of data blocks, a data block including selected ones of the plurality of data elements, the selected ones chosen in response to user-selected parameters; process the plurality of data blocks in an order specified by a user, to yield processed data corresponding to each data block of the plurality; reassemble the processed data corresponding to each data block to form output data corresponding to the input data; and output the output data from the processing block to another block of the block diagram.
 11. The computer-readable storage media of claim 10 wherein the plurality of data elements of the input data are organized as a matrix having a first set of dimensions, and the one or more data elements of at least some data blocks are organized as a matrix having a second set of dimensions that are smaller than the first set of dimensions.
 12. The computer-readable storage media of claim 11 wherein the user-selected parameters include at least one of a user-selected number of rows or a user-selected number of columns, that define the second set of dimensions.
 13. The computer-readable storage media of claim 10 wherein a particular data block is associated with a unique codeword, and the code is further executable by a computer to: generate an address of a data element included in the particular data block using the unique codeword associated with the particular data block.
 14. The computer-readable storage media of claim 13 wherein the unique codeword is a linear function that may be represented in the form f(i)=a+bi, where f(i) is the address of a data element, a is a starting index, b is an index increment, and i is an index of iteration.
 15. The computer-readable storage media of claim 10 wherein the input data is partitioned according to a user-selected range that specifies a portion of the input data to be partitioned into the plurality of data blocks.
 16. The computer-readable storage media of claim 10 wherein at least some data elements of a first data block are also included in a second data block.
 17. An apparatus comprising: a processing block configured to receive input data including a plurality of data elements, the processing block including, a selector configured to select data blocks in an order specified by a user, a data block including selected ones of the plurality of data elements of the input data, a data processing unit coupled to the selector and configured to process the selected data blocks in the order, to yield processed data corresponding to each data block, an assignment unit coupled to the data processing unit and configured to arrange the processed data corresponding to each data block in a particular arrangement to form output data corresponding to the input data, and an output configured to pass the output data to another block of the block diagram.
 18. The apparatus of claim 17 wherein the plurality of data elements of the input data are organized as a matrix of a first size, and the one or more data elements of at least some data blocks are organized as a matrix of a second size.
 19. The apparatus of claim 18 wherein at least one of a user-selected number of rows or a user-selected number of columns define the second size.
 20. The apparatus of claim 17 wherein a particular data block is associated with a unique codeword, and the apparatus further comprises: an index generator configured to generate the unique codeword of the particular data block.
 21. The apparatus of claim 20 wherein the index generator is further configured to use the unique codeword of the particular data block to generate an address a data element included in the particular data block.
 22. The apparatus of claim 21 wherein the unique codeword is a linear function that may be represented in the form f(i)=a+bi where f(i) is the address of a data element, a is a starting index, b is an index increment, and i is an index of iteration.
 23. An apparatus comprising: means for receiving input data at a processing block of a block diagram, the input data including a plurality of data elements organized into an arrangement having at least two rows and at least two columns of data elements; means for partitioning at least a portion of the input data into a plurality of data blocks in response to user-selected parameters, a data block including selected ones of the plurality of data elements; means for performing a data processing function on the plurality of data blocks in an order specified by a user, to yield processed data corresponding to each data block of the plurality; means for reassembling the processed data corresponding to each data block to form output data corresponding to the input data; and means for outputting the output data from the processing block to another block of the block diagram.
 24. The apparatus of claim 23 further comprising: means for generating a unique codeword for a particular data block of the plurality of data blocks; and means for using the unique codeword of the particular data block to generate an address of a data element included in the particular data block.
 25. The apparatus of claim 23 wherein the selected parameters comprise at least one of a user-selected number of rows or a user-selected number of columns, that define a size of a data block. 